New for the 2017 model year, the intake is marked by a hood scoop and is said to provide most of the air — around 60% — going into the engine. The rest comes from a dry location in one of the front fenders and enters via the air filter housing.
Because of the intake’s design, the air going into the engine is prevented from being heated by the warm conditions under the hood.
This results in better overall performance, especially in conditions where engine and transmission temperatures rise quickly. And there’s also a performance gain when driving on the highway thanks to a ram-air effect from the incoming air.
Testing conducted 11,000 feet above sea level
But the air also needs to be dry. That’s why the intake features an air/water separator where humidity or mist is turned into larger, heavier droplets that can be collected from the air before entering the engine.
“While developing this all-new induction system, we considered our customers towing a maximum-weight trailer through the Eisenhower Tunnel on a hot, rainy summer day,” Silverado HD chief engineer Eric Stanczak explained.
Eisenhower Tunnel, which carries Interstate 70 through the Rockies, is 11,000 feet above sea level, making it the highest vehicle tunnel in the world.
The diesel fitted to the Silverado 2500HD is a turbocharged 6.6-liter V8. It produces 397 horsepower and 765 pound-feet of torque and can tow as much as 18,000 pounds.